Writing for The Conversation, a website devoted to journalism by academics and those in research institutes, Dr. Bella DePaulo of the University of California, Santa Barbara argues that “instead of fretting” about the rising number of single people in the U.S. and around the world, “maybe we should celebrate.”

In her decades of research on the topic, DePaulo claims, she has discovered that singleness is “a boon to our cities and towns and communities, our relatives and friends and neighbors." Single people tend to reach out to friends, family, and neighbors more, “enroll in more art and music classes, and go out to dinner more often than people who live with others.” And what about all of those studies that we’ve seen over the years demonstrating that married people are healthier, wealthier, and happier than single people? DePaulo dismisses them as “exaggerated,” citing a handful of scholarly work demonstrating her point.

But in spite of such claims, research continues to build demonstrating that art classes and dinners out do not, in fact, fill in for a spouse and children.

The media and popular entertainment often depict the single life as glamorous and carefree. Such favorable depictions of the single life look rather dubious in light of a new German study concluding that unmarried men and women are distinctively vulnerable to loneliness and related psychological and physical illnesses.

Authored by scholars at Johannes Gutenberg University, the new study investigates “loneliness . . . as a risk to mental and physical health” among German adults. The researchers note that earlier studies have linked loneliness to “many negative mental health outcomes, such as depression, suicidality, reduced positive emotions, poor sleep quality and general health.” The physical health problems associated with loneliness identified in these earlier studies include “defective immune function and [increased] blood pressure” and the psychological problems include “reduced self-esteem and decreased coping.”

Not surprisingly, earlier studies have limned a connection between loneliness and “low life satisfaction and low resilience—particularly in men.” Earlier research has also shown that “loneliness . . . aggravates the morbidity and mortality of cardiovascular, cerebrovascular, and other chronic diseases” and is “related to cognitive decline and Alzheimer’s disease in aging.” At a time when medical costs are soaring in many aging countries, it is disturbing that earlier researchers have also concluded that loneliness is “associated with physical inactivity, smoking, and multiple health risk behaviors."

To gauge the effect of loneliness on 21st-century Germans, the researchers pore over data collected between 2007 and 2012 from a large and nationally representative sample of 15,010 adults between the ages of 35 and 74. Using a statistical model that accounts for demographic differences in age, gender, socioeconomic status, and employment, the researchers calculate that those experiencing loneliness are nearly twice as vulnerable to depression as those free from loneliness (Odds Ratio of 1.91). Among the study participants reporting depression, the researchers find a high prevalence of “generalized anxiety and panic attacks.” No wonder the researchers find that, compared to those free from loneliness, the study participants experiencing loneliness were over a third again more vulnerable to suicidal thoughts (Odds Ratio of 1.35). Further analysis revealed that, compared to peers free from loneliness, lonely adults were more likely to smoke and to visit physicians frequently (p < 0.0001 for both comparisons).

Inevitably, patterns of home life heavily affect loneliness. Among the study participants that the researchers identify as most likely to experience loneliness are those “without a partner or without children” (p < 0.0001 in comparisons with peers with partners and peers with children). The researchers report that less than one in thirty men and less than one in fifteen women living with a partner complained of loneliness (maximal values of 2.7% and 5.9% respectively). In sharp contrast, though it varies by age group, the incidence of loneliness runs between 10% and 20% among study participants living alone.

And though feminists have often encouraged women to steer clear of—or bail out of—marriage, the researchers find that women living alone are decidedly more likely than men living alone to feel lonely. The researchers limn the pattern by age group: “Women living alone in the age range 35-44 years (20.7% vs. 13.9%) and 55-64 years (19.3% vs. 11.6%) were considerably more affected by loneliness than men.”

At a time when marriage rates and fertility rates are low in Western Europe, while divorce rates remain relatively high, the authors of the new study have every reason to assert in their conclusion that “loneliness poses a significant health problem for a sizeable part of the population with increased risks in terms of distress (depression, anxiety), suicidal ideation, health behavior and health care utilization.”

Even round-the-clock viewing of episodes of Famously Single or Single Ladies may not make these issues go away.